From owner-freebsd-amd64@FreeBSD.ORG Sun Feb 1 16:49:10 2004 Return-Path: Delivered-To: freebsd-amd64@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 047FA16A4CE for ; Sun, 1 Feb 2004 16:49:10 -0800 (PST) Received: from dragon.nuxi.com (trang.nuxi.com [66.93.134.19]) by mx1.FreeBSD.org (Postfix) with ESMTP id BD93743D54 for ; Sun, 1 Feb 2004 16:49:07 -0800 (PST) (envelope-from obrien@dragon.nuxi.com) Received: from dragon.nuxi.com (obrien@localhost [127.0.0.1]) by dragon.nuxi.com (8.12.10/8.12.9) with ESMTP id i120n7A0094870; Sun, 1 Feb 2004 16:49:07 -0800 (PST) (envelope-from obrien@dragon.nuxi.com) Received: (from obrien@localhost) by dragon.nuxi.com (8.12.10/8.12.10/Submit) id i120n62U094869; Sun, 1 Feb 2004 16:49:06 -0800 (PST) (envelope-from obrien) Date: Sun, 1 Feb 2004 16:49:06 -0800 From: "David O'Brien" To: "Haapanen, Tom" Message-ID: <20040202004906.GA60117@dragon.nuxi.com> References: Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.4.1i X-Operating-System: FreeBSD 5.2-CURRENT Organization: The NUXI BSD Group X-Pgp-Rsa-Fingerprint: B7 4D 3E E9 11 39 5F A3 90 76 5D 69 58 D9 98 7A X-Pgp-Rsa-Keyid: 1024/34F9F9D5 cc: amd64@freebsd.org Subject: Re: Dual processor, AMD 64 machine freezing. X-BeenThere: freebsd-amd64@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list Reply-To: obrien@freebsd.org List-Id: Porting FreeBSD to the AMD64 platform List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 02 Feb 2004 00:49:10 -0000 [ Tom, PLEASE don't top-post -- it looses context in follow ups ] On Sun, Feb 01, 2004 at 06:34:10PM -0500, Haapanen, Tom wrote: > P.S. For best performance, I think you really want to run 4x 512 MB. > Running with two DIMMs means either you only get 64-bit memory access (not > 128-bit) or else you need to put both DIMMs into the CPU1 memory slots > (which means CPU2 will have to access those through hypertransport). ... > From: Mark Sergeant [mailto:msergeant@snsonline.net] > 2 x 1GB sticks PC 2700 ECC ram Tom is very correct -- you want to populate memory in pairs per CPU. This is so you can use both channels of the DDR memory controller. If you only put one DIMM per CPU, you're missing 1/2 your potential bandwidth. Consult your motherboard manual to determine which DIMM slots make up a pairing, not all motherboards are the same. Also, you want to spread your memory out across all your CPU's to get max performance. Look in the freebsd-amd64 archives for where I've detailed it more. -- -- David (obrien@FreeBSD.org)